Malignant melanoma is the most rapidly increasing cancer in Caucasians throughout the world. The increased incidence is due to greater sun exposure arising from changes in clothing habits and life-styles over the past fifty years. Most melanomas arise in preexisting moles in sun-exposed sites and may spread rapidly via the vascular system if not detected and removed early. Treatment of disseminated disease is unsatisfactory, with most patients dying of refractory brain metastases.